import java.util.ArrayDeque;
class MyStack {

    private ArrayDeque queue;

    public MyStack(){
        queue = new ArrayDeque();
    }


    /** Push element x onto stack. */
    public void push(int x) {
        queue.add(x);
    }
    
    /** Removes the element on top of the stack and returns that element. */
    public int pop() {
        return (Integer) queue.removeLast();
    }
    
    /** Get the top element. */
    public int top() {
        return (Integer) queue.getLast();
    }
    
    /** Returns whether the stack is empty. */
    public boolean empty() {
       return queue.isEmpty();
    }
}

/**
 * Your MyStack object will be instantiated and called as such:
 * MyStack obj = new MyStack();
 * obj.push(x);
 * int param_2 = obj.pop();
 * int param_3 = obj.top();
 * boolean param_4 = obj.empty();
 */